Methodological Guide on Environmental Sustainability Methodological_Guide | Page 7

Strategic Partnership Project (Key action no 2)
“ACTIVE CITIZENSHIP AND ENVIRONMENTAL AWARENESS THROUGH FORMAL
AND NON-FORMAL EDUCATION” (ACEAFNE)
connection between water and the products that we use? After a few students share their ideas,
divide students into small groups. Tell them:
Each group will get a set of cut-out cards with different products. To make all these
products, water is used in the process. Your task will be to put the cards in the order depending on
how much water you think is used to make the products. The most water intensive products will be
at one end, the least water intensive products at the other. You should consider all stages of
production and all the inputs.
Then hand out the cut-out cards with the products (Worksheet No. 1).
2/ Class discussion (5 minutes)
After a few minutes, ask students the following questions. (Don‟t reveal the correct answers
yet): Which of the products on the cards do you think needs the most water to be produced? Why?
And which one do you think is the least water intensive? How much water (how many litres) do
you think is used to produce some of the products?
Don‟t spend too much time discussing various products, as you will talk about the results
later in the lesson.
3/ Mathematical tasks (5-10 minutes – depend if one uses the math task or not)
Tell students that now they will learn more about how much water is needed to produce
those products. Each group will get a description of one of the products they have just discussed
that includes a mathematical task (Worksheet No. 2). First, they read the information about the
product in a group and then calculate how much water is needed to produce it. Distribute the tasks
so that each group is working just with one. If you have enough time or if some groups are faster
than the others, you can give them more than one task to read and solve.
In case you do not find the mathematical tasks appropriate for your students or you would
need more time for them, have the students work with the texts only – they can read them without
completing the task and can just share important information. After that, inform them about the
amount of water needed for each of the products.
Note: While the groups are working on their tasks, draw a long line on the board and indicate
the number of litres showing the correct answers from the tasks you gave them (not revealing yet
which belongs to which product):
0 litres _10__ 30 ______1,600 ________3,000__________ 15,000 Litres
4/ Class check (5 minutes)
When all the groups finish, ask them to write the products from their tasks by the respective
numbers on the line on the board. This way, they will check whether they have done the
calculations correctly and at the same time everybody will see the order of the products according
to their water intensity.
Key to mathematical tasks:
Rice: 2,300 / 0.67 = 3,432 litres = approx. 3,400 litres
Sugar: 175 / 0.11 = 1,590 litres
Tea: 2,400 / 0.26 x 0.003 = 27.69 litres = approx. 30 litres
Paper: 6,000 / 10 / 300 x 0.005 x 1,000 = 10 litres
Cotton: (3,600 / 0.35 / 0.9 + 30 + 140 + 190) x 0.25 = 2,947 litres = approx. 2,900 litres
At this point, add also the products from the cut-out cards (Worksheet No. 1) to compare
how water intensive they are:
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